Convertible sewing and darning machine



5 Sheets-Sheet l R. K. HOHMANN ETAL CONVERTIBLE SEWING AND DRNING MACHINE Filed Dee. 29, 1959 I A' itiii Juy 1, 1941.

JUIHY L 39M R. K. Hol-:MANN ETAL. 2,247,379

CONVERTIBLE SEWING AND DARNING MACHINE Filed Dc.v 29, 1939 3 sheets-sheet 2 July l, 1941.

R. K. HQHMANN ETAL. CONVERTIBLE SEWING AND DARNING MACHINE Fi'ledbeo. 2,9, 1939 s sheets-sheet s Richard K. Ho

(Osa, te Fla Roebuck and Co., Chi New York ica and Frederick cra to de. a corporation oi application necemter aa, ieee, sei-iai No. annee i2 cias. (ci. ira-iai) The general object of our present invention is to provide a simple and eiective sewing machine adapted iur interchangeable use as a darning hine and for. ordinary sewing operations.

One specic object of theI invention is to provide a sewing machine which is readily convertible from one to the other of two conditions in one of which it is adapted for plain sewing and includes a dat work bed, which may .be generally similar in form and disposition to the conventional worir bed of a plain sewing machine, and in the other oi Awhich itis adapted -for darning and is'adapted to support stockings or other work to be darned, cna cylinder arm generally like, though preferably somewhat smaller in cross section than, the work supporting cylinder arms of ordinary darning machines. In its preferred form, the machine is adapted, however, for either plain sewing or darning operations-on flat bed and cylinder arm supported work.

Another specific object of the invention is to provide a sewing machine of the kind specied with a' presser bar mechanism readily adjustable between a plain sewing condition in which the presser foot-continuously engages the work, and a second darning condition in which the pressure bar is lifted between successive needle strokes.

Another specific object of the invention is to provide a presser bar actuating mechanism adjustable to give the presser .bar relatively low lift movements suitable for darning stockings or other thin material, and relatively high 4lift movements needed in darning blankets or other thick material.

Another speciiic object of the invention is to provide a novel work feed mechanism, especially' adapted for use in a sewing machine in which all of the underbed sewing instrumentalities are located in a hollow cylinder arm of relatively small cross section.

vantages and speciiic objects attained with its use, reference should be had to the accompany ing drawings and descriptive matter in which we have illustrated and described preferred .forms of embodiment of the present invention.

Of the drawings:

Fig. 1 is'an elevation, partly in section,

ment of the present invention;

Fig. 2 is an enlarged reproduction of a portion of Fig. l., showing parts in different relative positions;

Fig. 3 is a section on the line t--t of Fig. i with parts broken away and removed;

Fig. 4 is an .elevation on the plane indicated yby the line ll-6i of Fig. i, of the sewing machine head with its front cover plate removed;

Fig.. 5 is a section on the line @-5 of Fig. li; showing the presser bar lift adjusting Iprovisions in one position;

Figs. 6 and l are sections taken similarly to Fig. 5, showing said adjusting provisions in different positions;

Fig; Sis a perspective' View of the presser bar lifting and lift adjusting provisions;

Fig. 9 is a plan partly in section on the line t-a or ne. 1; R.

Another specic object of the invention is to A provide a pulley and belt drive connection'between a driving pulley mounted on the needle -bar shaft and a driving electric motor located inthe base of the sewing machine, and including provisions by which the portion of the belt above the base oi the l:machine is normally enclosed within the standard and adjacent arm portion of the machine, but may be made readily accessible for belt removable and replacement operation.

The various features of novelty which characterize the present linvention are pointed out with particularity in the claims annexed to and forming a part oi this specification. For a better understandlng of the invention, however, :lts ad- Fig. l0 is a section on the line id-lt of Fig. 1;

Fig. 11 is a partial section on the broken line lllll of Fig. l0;

Fig. 12 is a partial section on the line llii2 of Fig. 10;

Fig. 13 is a composite perspective view showing diierent work feeding mechanism parts;

Fig. le is a perspectiveview illustrating details of the main pulley-mounting;

Fig. 15 is a small scale elevation of a removable cover plate at 'the right hand end of the machine as shown in Fig. l.;

Fig. 16 is a perspective view of the removable hat bed part shown in Fig. l;

. Fig. 17 is a perspective view showing parts of Y the cylinder arm and hat work bed of Fig. 1 in section;

of asewing machine constituting a preferred embodlpulley B' on its shaft which is operatively connected by a belt C to a driving pulley D mounted l on theadjacent end of the needle bar shaft E,

which may be journalled in the arm A3 in any usual or suitable manner. In the preferred construction shown, the ,rear end E of the needle bar shaft E is threaded, and supports a nutmember F, which may be rotated about the shaft end E' to thereby clamp the hub portion of the pulley D between the 'head of the-nut member F and the radially extending iiange of a part E2 carried by and secured to the shaft E and comprising a tubular hub portion E3 forming an elongated bearing for the pulley D. When the nut F is backed ofi', as shown in Fig. 2, the pulley E may be displaced axially of the shaft E, from its` nor= mal position, to thereby move the inner, belt groove portion of the pulley out of its normal position within the arm A3 so as to permit the k'belt C to be removed from and replaced on said pulley. As shown, a washer member F' is interposed between the nut F and the hub of the pulley D, said washer member having integral arm extensions F" received in longitudinal slots formed for the purpose in the tubular portion E3 of the part E2.

At its head end, the shaft E carries a crankl disc E4 in which is mounted a crank pin Eri connected-by a link G' to a pivot pin G2 carried by 1n the third adjustment of 7 ing projection H or H2, and clockwise movements of the lever H will not lift the presserv bar.

When the member ha is given an up movement l by the lever H,v that up movement is normally transmitted to the presser .bar h through the engagement of the upper end of the member ha with an abutment member hfi clamped on the presser bar, and normally held by the spring h in engagement with part ha, in all positions of presser bar. As shown in Fig. d.' a manually adthe needle bar G, mounted in the head A4 in any usual or suitable manner for vertical reciprocatory movement. The needle barv G also carries a cam roller G3, which, on each up movement of the needle bar, gives a counterclockwise movement to a, bell crank lever I-I pivoted to turn about a horizontal pivot H and spring biased for counterclockwise movement as the needle bar descends. The horizontal arm of the bell crank lever H-comprises uprising projections H' and I-I2 at lesser and greater distances respectively,

from 'the axis of the lever H. vOrl each' needle bar upstroke, one, or the other, cor neither, of the projections H' and I-I2 is adaptednto operatively engage the vertically movable presser bar `hdependingon the angular adjustment of a member h* mounted on, and rotatable about the presser bar h. The bar h is normally biased for down movement by a spring hv'. u

A lever HA extending into the head A14 and pivotally connected through a .pivot HA', has a y bifurcated lower end straddung a. pin h3 dependlng from the upper portion of the member he,

"and laterally displaced from its axis, so that the justable cam lever HB is in the position in which it engages the part hf and holds the presser bar in an elevated position slightly abovel the high lift position into which it may be moved by the c projection H2 and arm h4 of the member h. In the normal position of the lever im, shown in dotted unes m Fig. 4, it permits the part h6 to,

bear on the member ha in all positions of the latter.

The sewing machine includes tension and thread takeup provisions which may be of conventional type and hence not requiring descrip@4 tion herein.

The sewing machine mechanism shown, is of the rotary hook type, and comprises a hook shaft I, which is suitably journalled in the frame part A and its cylinder arm extension A5, and which carries a loop taker or hook element i adjacent the front end of the machine. The hook shaft I is rotated by the needle bar shaft E through a vvertical shaft I' journalled in the standard A2 and having its upper end connected 'to the shaft E by bevel gears 122 and having its lower end connected to the hook shaft I throughbevel gears I3. Desirably, and as shown, .the gears are so proportioned that the shaft I will rotate lwith double the angular velocity of the shaft E.

The sewing machine includes work feeding means comprising a feed dog K adapted to ex'- tend up into and to move horizontally in the slot of a throat or needle'plate part KA, of conventional iiat form and supportedby the cylinder arm part A6. The work feeding means also comprises mechanism within the hollow cylindrical shown inFig. 7, its arm h* is in lposition to be k engaged and lifted by the projection I-l?l and thereby give ahigh lift to the presserbar, such as may be needed in darning blankets. In a section of the member L.

arm of the sewing machine for giving the feed dog its feeding movements. Said -mechanism comprises a cross head member L mounted in a guideway M' in a second cross head M for vertical movement relative to the latter. The feed dog Kis normally securedI to the upper end of the member L by screws. port L is given up and down movements by the angular oscillation of a shaft L5, which carries an arm including a. portion L parallel to, but

laterally displaced from the shaft L5, and entering a. horizontal `-slot formed in In the preferred construction shown, the shaft L5 is tubular and surrounds'an oscillating shaft The feed dog sup-v the upper pcrv M5 which carries at its front `ende. `crank Varm M6 supporting a pin MI parallel t and laterally displaced from the shaft .M5vg Thepin M" enters a ments through an arm L19 suitably formed opening M1 in the member M, which is mounted in the framework of the machine for horizontal-to and' fro movement in a direction transverse to the needle bar shaft and to the shafts M and L5. The mounting provisions illustrated comprise stationary guide pin portion of the member M, so shaped and disposed as to accommodate the oscillatory movements of the pin L6. Each of the members L and M is formed with an. opening for the t; t: of the hook shaft E large enough to accommodate the the feeding mech :.1 u; located within a cylinder vements of the parts L and M relative to that v shaft.

IThe shaft lid5 is oscillated to give the leed dos K its horizontal feeding movements, throush a cranlr arm 11 secured to the rear end ci the shaft M5 and an actuating lever M21 pivotally connected to the arm M20. The lever M11 has an upper end stradd a cam carried by the shalt E., n .roller pivotally m to the lever 1 is received in the eway in a member M111 which is l chine .includes a removable worh memher 1E,

arm of cross section.

ds shown in Fig. t, the shaft of the motor B is parallel to the needle har shaft E and hook shaft l, but ls laterally displaced from the latter. To accommodate this displacement without requiring the standard A2 to have an unconventional and undesirable forman idler N, normally encased by the rear oi the t. is

so located as to dehect the lower portion oi t belt run into or near parallelism with the heit iront which estenda in a action inclined to the vertical trom the pulley to the pulley D. In the nor opera tion, the upper portion voi the heit aroove in the pulley D is within and closely encircled -hy a cylindrical portionl .d10 or the irameworh. iin ope formed in the standard .d1 and at t e risht nd end of the rw w in il: l, is normally closed hy a removable cover plate ormemher A11. sho in outline in his. it. The removal oi the cover memr n ves a to the portion oi' the heit d other mm: ,f f s.: the hollow standard.

In the io shown in l. the sewins lnia-- shoin perspective in his. it. da sho in Y whiohgvrhen the wir: 1

pivotallyconnected to the standard d and is provided with a stitch adjusting arm M exten turn a slot in the side or the sdard A2,

so that the member may heus t t u larly in one action away -from a position which the suideway extends horizontally, into positions in which it is in c upwardly aw lfrom the horizontal position, and in e other direction into other positions lin which it is inclined downwardly away from the horizont.

With the slideway in the me v l horl zontally disposed, the oscillatory movements siven hy the shalt E to the upper end oi the lever will impart no oscillatory movement to the lower end oi the lever 1 or to the shalt l en the tree end of the M2 is moved downward to incline the deway downwardly from the horizontal, the feed doy K wmp@ given movements in the normal direction, i. e., awa

' and other worh. iis vcylinder may the upper end or the leverM21 will impart t.:

feed movente to the feed dos K, oi a l. l

depending onthe inclination of the t" v:

the horizontal. f

The shalt L'is given oscillatory movements and the iced dos K thereby given up and down move- .1 tothe rearend v.of the tubular shaft L5 and pivotally connected to the lower end of a link L21 which, on its upper end, carries an eccentric strap L32 surrounding an eccentric on the shaft E.

The means including the ansularly adjustable guide member through which the movements imparted hy the shaft E to the upper end of the lever Vton wall portion of the -t-` i :M it, the latter is in the iorm oi a metal minus its hottom wall and open at its end is in use as sho in Illia. i. is -adja t and hears ait theo f wir -maire part il. The P is termed with an openinar" in its top l to receive the tat plate memlnarl and with van nt o P3 partly in the top wall and rtly in the cl end member. The opening P11 is normally ci l' hy a s 1 r i ed cover emher P13, which when moved into open position, pets access to the hohhin oase extending into the loop ter, lor insertion at; reoval of hohloins. As shot' 1: the plate d is formed with an uprising ma L ae An in telescopic a sement with the lower portion ot the i, plate part P. whereby the latter is anchored in position. With the P in place, the machine as a whole, has the general appeace and operative cacity of an ordinary dat hed sewing mno. with thehed mcrnher ,P removed, the worh supmrt is oi thecylinder arm to heretofore` in awww-lt stoclrinss own in i7, c tubular ly4 he aenerally elliptical in cross section with its t ion attened to provide a dat t tor the ons 1P. f In lieu oi.` the dat worh lied part l? shown l, ld and il, l may mata use of the rh M21 give the feed dog K feeding vmovements in l the normal direction, or in the reverse direction,

l or hold the feed dog against horizontall movement, are oi a known type. The -feed mechanism bedpart Pn shown in Fiss. i8 and it. The part Pd (lidera from the vom P lnv'that it is rood with a lonaitudinal slot P10 ln its top wall'adapted to receive the flattened t0n Willi rtlon oi the cylinder arm d50. which to thisend may diiler in shape from the cylinder arm idrst described, in that its top wall portion is in the form oi a dat rib shaped to ilt into the slot P10. As shown, a bohbin winder wheel Q, carried by an arm Q' pivotally connected to the standard A2, is adapted to be turned from its idle position, shown in Fig. 3 into the position in which the wheel Q extends through a slot formed for the purpose in the standard A, and frictionally enwinding operation'is normally free to turn on the illustrated and described, is believedjto he novel needle shaft E.

The general operation of the i 1r a, machine illustrated and described, will be readily apparent to those skilled in the art. With either of the bed plate parts P and PA in place, and with the thrust member h.x3 out of position for operative engagement by the oscillating lever H, and with the member M25 adjusted through lts arm M26 into positipn to eiiect the desired worn feeding movements of the feed dosr K, the machine will operate as an ordinary plain sewing machine. When the thrust member he is adjusted into position for operative engagement by the oscillating lever H, and the guide member M25 is adjusted by the arm M26 into position torenoler the reed mechanism inoperative, the machine is adapted ior'operation like an ordinary dag machine. By adjusting the member he to vary the distance from the vertical plane including the anis of the lever H at which the lever operatively engages the member ha, the extent oi lift elven the presser bar may be varied in conformity with the character and particularly the thickness oi the work. In the plain sewing mode of operation, the position of the work is controlled by two elements,

namely, by the presser foot which continuouslyl engages the work and holds it in msition for intermittent engagement by the feed mechanism, whichconstitutes the second of said elements. lin the contemplated flaming mode of operation, the worn is free from position control by either ci the above mentioned elements during an interval between each two successive penetrations of the wol-ls by the needle, but the presser loot operatively engages the work at the beginning of, or"

before, each penetration of the worls by the needle.

As previously stated, the chine may be used interchangeably in plain sewing and darnlna operations, either with the dat bed rt P or PA in place, or removed so that the work may be supported on the cylinder arm. The hat parts l? and PA are simple in form and easily led August 3, 1940, and Serial No. 351,014, filed August 3, 1940.

While in accordance with the provisions of the statutes, we have illustrated and described the best form of embodiment of -the invention now known to us, it will be apparent to those skilled put in place and removed; In some operations,

for example, in repairing a childs sleeve ortleg which has a rip running into a hole, our iniproved machine may eiect the plain se and fr u portions of the repair operation needed,

one aim nie other, without any interruption or the reciprocatory movements or the and without any adjustment of the work relative to the cylinder arm4 work support, other than the 'suc advancement of the work by the iced mechainsin in sewing up the rip, the manual adjustment of the work during the dancing operation eilected'aiter the levers HA and M have been adjusted to respectively subject the presser foot to the lifting action ot the lever H, and to interrupt the horizontal movement of the feed dog K, The driving connection between the motor and the needle shaft is relatively simple, and the belt removal and replacement operations are simple and of a character to be readily performed by theordinsry housewife. AThe sewing machine shown is of the'portable time. but our improvements disclosed and'clsimed herein are adapted ,Nm 348,928, filed July 13, 1940, Serial N0. 351,013,

in the art that changes may be made in the form ofthe apparatus disclosed without departing from the spirit of the invention as set forth in the appended claims and that in some cases certain features of our invention may be used to advantage without a corresponding use of other features.

Having now described our invention, what we claim as new and desire to secure by Letters Patent, is:

l. i sewing machine adapted for interchangeable use in plain sewing and darning operations and including in combination a frame, and mechanism mounted in said frame and comprising needle reciprocating means, cooperating stitch lforming mechanism, feed mechanism, means to make said feed mechanism operative or inoperative, a presser foot above said feed mecha, and means controlling the position of said presser foot and selectively operable to maintain said presser foot in position to continuously' engage work interposed between sal'd presser foot and feed mechanism, or to operatively connect said presser foot to said needle reciprocating means and therebylcause said presser to be lifted out of its work engaging position in synchronismY with the reciprocatory movements of the needle.

2. A sewing machine adapted for interchangeable use in plain sewing and darnlna operations and including in combination e, fre, and mechanism mounted in said frame and comprising needle reciprocating means, cooperating stitch forming mechanism, feed mechanism, means to make said feed mechanism operative or inoperative, a presser foot above said feed mec and biased for continuous engagement with work interposed between said presser loot and feed meism, lifting means adapted, when operative, to lift said presser foot out of and permit it to return into engagement with the work in synchronlsm with the needle movements, and means for rendering said lifting means inoperative.

3. A sewing machine adapted for d op- @rations d comprising in combination a trame and mech mounted therein and comprisme a needle reciprocating means,A cooperating stitch forming mechanism, a presser bar and foot` "l having a thrust surface, and means adapted to lift said presser foot out of and return it into its work engaging4 position in synchronism with the reciprocatory needle movements comprising a lever arm pivoted to said frame to turn about a. horizontal axis and operatively engaged by said needle reciprocating meenstooscillate said lever arm about said axis in timed relation with the reciprocatory movements ol' the` needle, and

including adjusting means operable to vary the leverage with which' said lever ,arm acts on said 'thrust surface.

l 5. A sewing mschinesdapted for interchangeg able use in plain sewing' and darning operations and including in combination a frame and mechanism mounted in said frame and comprising needle reciprocating means, cooperating stitchforming mechanism, feed mechanism, means to make said feed mechanism operative or inoperative, a presser bar having a presser foot and biased for continuous engagement of said foot with the work, a lever actuated by the needle reciprocating'means to oscillate in synchronism with the needle movements abouta horizontal axis, and a thrust member mounted on said presser bar for angular adjustment about the latt-er into one position in which it is engaged 'by said oscillating lever at a predetermined. distance from said axis to give relative high lifting movements to said presser bar, and into a second position in which said member is engaged by said oscillating lever at a distance from said axis less than the irst mentioned distance to give relatively low lifting movements to said presser bar.

6. A sewing machine adapted for interchangeable use in plain sewing and darning operations and including in combination a frame, and mechanism mounted in said frame and comprising needle reciprocating means, cooperating stitch forming mechanism,v feed mechanism, means to make said feed mechanism operative or inoperative, a presser bar having a presser foot and biased for continuous engagement of said foot with the work, a lever actuated by the needle reciprocating means to oscillate in synchronism with the needle movements about a horizontal axis, and a thrust member mounted on said presser'bar for angular adjustment about the latter into three predetermined, different positions, and adapted in one position to be engaged by said oscillating lever at one distance from said axis to thereby give relative high lifting movements to said presser bar, and in a second of said positions to be engaged by said oscillating lever at a distance less :than the first mentioned distance from said axis and thereby gives relatively low lifting movements to said presser bar, and when in the third position being out of operative engagement with said lever, so that the oscillations of the latter do not then lift the Prser bar.

7. A sewing machine as specied in claim 1, in which the said means selectively operable to control :the position of said presser foot comprises an actuating lever pivoted on said frame and accessible for ready adjustment by the sewing machine user to predetermined angular positions.

8. A sewing machine adapted for darning operaticns and including in combination a frame and mechanism mounted in said frame and comstitch forming mechanism, a presser bar having a thrust surface and a presser foot and means adapted to lift said presser foot out of and return it into its work engaging posi-tion in synchronism with the reciprocatory movements com- Pricing a lever arm plvoted to said frame to turn about a horizontal axis displaced laterally from the presser bar, and operatively engaged by said needle reciprocating means and thereby oscillated pricing needle reciprocating means, cooperating 9. A sewing machine as specified in claim l in which the said means selectively operable to control the position of said presser foot comprises an actuating lever pivoted on said frame and accessible for ready adjustment by the sewing machin-e user to predetermined angular positions and positioning means associated with said lever and determining the diierent angular positions of the lever and tending to maintain the latter in each of said positions into which it is adjusted.

10. A sewingmachine as specied in claim 1, in which the said means to make said feed mechanism operative or inoperative, comprises an actuating lever pivoted on said frame and accessible for ready adjustment by the sewing machine user to render said feed mechanism operative or inoperative, and in which the said means controlling the position of the presser foot comprises an actuating lever accessible for ready adjustment by the sewing machine user to predetermined angular positions.

11. A sewing machine adapted for interchangeable use in plain sewing and darning operations and comprising in combination a frame includ-ing a standard, overhanging arm an-d needle head, a vertically4 reciprocating needle bar mounted in said head, a presser bar mounted in said head back of said needle bar and having a thrust.

surface, a lever at the side of said bars remote from said standard and pivoted to said frame to turn about a horizontal axis parallel to said arm and in front of sai-d presser bar, means carried by said needle bar engaging said lever and loscill-ating the latter on each reciprccation of the needle bar, and a member adjustable into and out of an operative position in which it forms a thrust connection between said lever and presser bar thrust surface lifting the presser bar on each oscillation of the lever.

12. A sewing machine adapted for interchangeable use in plain sewing and darning operations and comprising in combination a frame including a standard, voverhanging arm and needle head, 'a vertically reciprocating needle bar mounted in said head, a presser bar mounted in said head back of said needle bar, and having a thrust surface, a lever at the sides of said bars remote from said standard and pivoted to said frame to turn about a horizontal axis' parallel to said arm and in front of said presser bar, means carried by said needle bar engaging said lever and oscillating the latter on each reciprocation of the needle bar, a member forming a thrust connec- .lever respectively engages said member at greater and lesser distances from said axis.

RICHARD K. HOHMANN. FREDERICK OSANN. 

